function polar = gcpick_pickpolar(options)
polar.E = 0;
polar.N = 0;
polar.Z = 0;
disp('Polar:');
loc = contains(options, 'e');
if sum(loc) == 1
    t = sign(str2double( options{ find(loc)+1 } ));
    if ~isnan(t)
        polar.E = t;
    else
        disp('E polar is NaN');
    end
elseif sum(loc)<=0
else
    disp('More than one E polar is set');
end
loc = contains(options, 'n');
if sum(loc) == 1
    t = sign(str2double( options{ find(loc)+1 } ));
    if ~isnan(t)
        polar.N = t;
    else
        disp('N polar is NaN');
    end
elseif sum(loc)<=0
else
    disp('More than one N polar is set');
end
loc = contains(options, 'z');
if sum(loc) == 1
    t = sign(str2double( options{ find(loc)+1 } ));
    if ~isnan(t)
        polar.Z = t;
    else
        disp('Z polar is NaN');
    end
elseif sum(loc)<=0
else
    disp('More than one Z polar is set');
end
fprintf('e:%d, n:%d, z:%d\n', polar.E, polar.N, polar.Z);
end